--- Sean Cunningham <[EMAIL PROTECTED]> wrote:
> I have very large datasets and have found that the built in union,
> intersect, and except operations do not seem to use indices
> (would be happy to be proven wrong here). As such, they
> are not very speedy with large large data sets.
A
On 6/18/07, Sean Cunningham <[EMAIL PROTECTED]> wrote:
There was talk in the mailing list a while back about creating a new
operator that would act as a superset of '==' which would treat
NULL==NULL as True. I have seen this in some other database.
Anybody know if this is on the roadmap?
It
On Jun 15, 2007, at 5:27 PM, Scott Hess wrote:
select tableA.path, tableA.value from tableA,tableB where
tableA.path=tableB.path and tableA.value=tableB.value union
select tableA.path, tableA.value from tableA,tableB where
tableA.path=tableB.path and tableA.value IS NULL AND tableB.value IS
> select tableA.path, tableA.value from tableA,tableB where
> tableA.path=tableB.path and (tableA.value=tableB.value or
> (tableA.value IS NULL AND tableB.value IS NULL));
>
> It's possible that won't use an index, either, due to the OR, in which
> case you could try a union between a select with
You can use something like:
select tableA.path, tableA.value from tableA,tableB where
tableA.path=tableB.path and (tableA.value=tableB.value or
(tableA.value IS NULL AND tableB.value IS NULL));
It's possible that won't use an index, either, due to the OR, in which
case you could try a union
sqlite-users@sqlite.org
Sent: Friday, June 15, 2007 1:26:49 PM
Subject: [sqlite] Optimization of equality comparison when NULL involved
I am hoping there is an obvious answer to this that I've overlooked.
I have two tables:
create table tableA (path TEXT, value TEXT);
create index myIndexA on tableA
I am hoping there is an obvious answer to this that I've overlooked.
I have two tables:
create table tableA (path TEXT, value TEXT);
create index myIndexA on tableA (path, value);
create table tableB(path TEXT, value TEXT);
create index myIndexB on tableB (path, value);
Now some simple
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